Insect scientists say biotech corn is losing its ability to fend off a major insect pest known as the corn rootworm. The scientists say continued widespread use of genetically-modified corn will only make the problem worse.
Scientists say the corn rootworm is becoming resistant to Bt corn, a crop genetically-engineered to protect against the pest.
Earlier this week, 22 scientists wrote a letter to the Environmental Protection Agency expressing their concerns. University of Illinois insect behaviorist Joseph Spencer was one of them.
He says farmers can't just rely on a single pest management strategy.
“We can't rely on just Bt. We need to think about using a mix of techniques to assure that we can protect the corn that we're growing in the United States,” Spencer said.
Monsanto, which makes Bt corn, says less than 0.2 percent of the acres planted with its corn variety experienced pest damage last year.